The mechanisms of the biosynthetase reaction catalyzed by the Mg2 ion supported unadenylylated glutamine synthetase from E. coli has been elucidated to show the complete catalytic cycle. In addition to the enzyme-substrate and enzyme-product complexes, the cycle consists of two fluorescent intermediates. The proposed mechanism is used to explain the observed pH profile and the inhibition exhibited by amino acids. Two amino acid binding sites are proposed, one for L-amino acid and one for D-amino acid; Gly binds to both sites. L-amino acids can bind weakly to the D-amino acid site and vice versa. Binding to the L-amino acid site inhibits the reaction between intermediate 2 and NH3, whereas the binding to the D-amino acid site will antagonize the binding of glutamate. Theoretical analysis of a regulatory model which involves covalent modification of enzyme shows that a cyclic cascade regulatory system constitutes remarkable potential for both positive and negative allosteric control with tremendous amplification potential. In essence, a controlled cascade system functions like a physiological computer. Other work includes lag-time study, fast kinetics of substrate binding, actomyosin ATPase catalytic cycle, assay methods for adenylylation-deadenylylation, interaction of actin and phalloidin, isolation of ATase, PII, and glutamate synthase, improvement of stopped-flow machine and development of laser heating temperature jump machine.